Employing quantitation of radiolabeled mucous glycoprotein secretion from cultured human airways, the effects of HETEs, SRS-A (leukotrienes C and D), leukotriene B, and steroids were examined. The synthesis of HETEs by human airways was verified. The effects of prostaglandin generating factor of anaphylaxis (PGF-A) on prostaglandin synthesis by human airways (peripheral and central), pulmonary arteries and veins, and peripheral lung tissue were examined. The roles which the eosinophil and neutrophil play in the generation of late-phase reactions was studied. The histamine receptor subtype on mast cells, as well as the beta adrenergic receptor in both mast cell membranes and perigranular membranes, were characterized. The response of humans to histamine infusions, both in regards to physiologic responses and the receptor subtypes involved, were characterized. The quantitative relationship between autoantibodies to beta adrenergic receptors and autonomic nervous system responsiveness was determined. The assay for histamine in plasma and urine has been made more sensitive. Employing the urine histamine assay, the pathogenesis of reactions to radiocontrast media are being explored. The presence of opiate receptors on rat and human mast cells was examined.